Process of bleaching vegetable fiber and fabrics.



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REINl-IOLD GRT TTER, OF OHAELOTTENBUEG, GERMANY, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO B. H. COMEY COMPANY, OF CAMDEN, NEW JERSEY, A CORPORATION OF NEW JERSEY.

No Drawing.

Specification of Letters Patent.

Patented June 3, 1913.

Application filed June 3, 1911. Serial No. 631,113.

To all whom it may concern Be it known that TfRnrierroLD Gar'irnn, a citizen of the German Empire, residing in Charlottenburg, near Berlin, in said Empire, have invented certain new and useful Improvements in Processes of Bleaching Vegetable Fiber and Fabrics, of which the following is a specification.

This invention relates to an improved process of bleaching vegetable fiber and fabrics.

It was discovered by practical tests that vegetable fiber and fabrics could be bleached in the most perfect manner and without the least impairmentof the fiber by first treating them with hydrogen peroxid,

and then subjecting them to the action of ammonia-vapors.

By the first step, namely the treatment of the hydrogen peroxid, no essential bleaching effect is obtained on the fiber; but as soon as the so treated fiber is subjected to the action of ammonia-vapors, the hydrogen peroxid absorbed by the fiber is decomposed in a very short time and oxygen separated with considerable foaming. During the short time taken up by the reaction an intense bleaching effect is exerted on the fiber.

Example: A Panama hat or other fabric is first washed with soap water and then dried. It is then submerged in a 15% solution of hydrogen peroxid, which is heated to about 70 (1., the fabric remaining in the solution until it is saturated. This is usually accomplished in a few minutes. Inas much as concentrated solutions of hydrogen peroxid lose at the temperature referred to, especially when covered with dirt or other impurities, in consequence thereof some of their oxygen, it is advantageous to add for bleaching purposes a small quantity of a tin compound, such as for instance tin sulfate. A fraction of 1% is sufiicient, as thereby a reliable boiling resistency of the peroxid solution is obtained. The fabric to be treated is then removed from the solution, the excess of the solution expressed from the material, and, while still hot, introduced into an atmosphere of ammonia-vapors contained in a closed chamber. Thls atmosphere must be obtained by suspendlng the fabrlc over a'concentrated ammonia-solution and heating the same so as to accelerate the generation of ammonia-vapors. The hotter and stronger the ammonia-vapors are and the hotter the fabric is when treated, the quicker and stronger is the bleaching effect obtained. Under favorable conditions the fabric is fully bleached even within a few minutes.

The process of treating the vegetable fiber or fabrics can also be reversed, namely, by impregnating the same in suitable manner with ammonia or substances which split off ammonia, and then subjecting them to the action of hydrogen peroxid.

The process described has the advantages that a very high degree of bleaching is obtained; that a very small quantity of bleach ing material is required; that the bleaching is effected within a very short time; that it can be accomplished at a greatly reduced cost and without impairing the fiber or fabric in the least. Furthermore, the bleaching effect is obtained uniformly over the entire fiber or fabric to be bleached.

I claim:

1. The process herein described of bleaching vegetable fiber and fabrics, which con- Y subjecting them while in highly heated coning fibrous material, which consists in satu- In testimony that I claim the foregoing as ratmg the materlul wlth a solutlon of hymy lnventlon, I have slgned my name 111 drogen peroxld \VhlCh 15 free of decompospresence of two subscrrblng wltnesses. mg matter, removlngthe excess of the solu- REINHOLD GRUTER 5 tlon from the materlal, and exposmg the fit same to a yapol of ammonla, Inch "211301 15 MAX MAETSUI'HW, contzuned 111 a chamber. PAUL FENGLEN Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. G. 

